"Compulsion"
means the use of physical force, a threat to use physical force or a combination
thereof that makes a person unable to physically repel the actor or produces
in that person a reasonable fear that death, serious bodily injury or kidnapping
might be imminently inflicted upon that person or another human being.

Maine refers to persons
who cannot possess firearms (and even crossbows) as “prohibited persons”.The statute
on that issue is here, in title 15:

There are some
33 statutes within title 12 that regulate the possession, use and transport
of firearms, including discharge near structures, possession on certain game
preserves and parks, transportation on Sunday, transportation in motor vehicles
and possession of a firearm on a paved way.

Moreover, there
are regulations issued under the authority of the laws.The regulations must also be obeyed.The Title 12 regulations are contained here:

The National
Firearms Act, the 1968 Gun Control
Act, as well as the laws relating to interstate transportation (Firearm Owners Protection Act of 1986) and possession of weapons on
federal property, are contained in title 18 of the United States Code (USC).